Durability

Over the head, around the neck, the one-hand-single-ear hold — DJs constantly twist and forcefully form fit headphones, and a proper pair should be able to take the abuse (at least for a year or two). Check how strong the joints / hinges are and the quality of the materials used.

Comfort

However you wear them, DJ headphones should be comfortable. Check for headband padding, quality of the ear pads, and adjustability. Further, swiveling or rotating cups might provide better fit, and if you like to move around in the DJ booth, look for headphones with coiled and/or detachable cords.

Single Cord Design

If the headphones have two cords coming from the ear pieces, they're not DJ headphones. DJ headphones always have single cord design for less tangles and booth accidents.

Folding Design

Do they fold into a portable shape? How easy is it to stuff them into your bag (with limited space) at the end of the night? Headphones that don't fold tend to break during transport.